#include <iostream>
using namespace std;
int main()
{


void myprint(int,int);
void myprint(char,char);
    int a,b;
    char m,n;
cin>>a>>b>>m>>n;
myprint(a,b);
myprint(m,n);

return 0;



}

void myprint(char a,char b)
{
    char c=0;
    int m;
    b=int(b-a);
    if(a>=0) 
        cout<<"Error";
    
    else
        for(int n=0;int(n+a)<int(b);n++)
        {
            cout<<char(a+n);
            if(n%8==0&&n!=0)
                cout<<endl;
  
        }
}


void myprint(int a,int b)
{
    int c=0;
    int m=0;
    c=int(b-a);
    if(c<=0) 
        cout<<"Error";
    
    else
        for(a;a+m<=b;m++)
        {
            cout<<char(a+m)<<"\t";
            if(m%8==0&&m!=0)
                cout<<endl;
            
            
        }
}